1. Field of the Invention
The present invention relates to an ablation method in which a tissue of a subject is heated or cooled.
2. Description of the Related Art
Thermal treatment called ablation in which a tissue of a living object such as a human body, which is a subject, is heated or cooled to degenerate the tissue or cells is known.
As an example of the type of ablation in which a tissue is heated, a method in which a tissue is subjected to, e.g., application of a high-frequency voltage such as microwave or radio wave, focused ultrasound irradiation or laser irradiation to make the tissue produce heat is known. Also, as an example of ablation in which a tissue is cooled, a method in which a tissue is cooled and frozen using a low-temperature liquid such as liquid nitrogen and vaporization phenomenon of such liquid is known.
As an example of ablation, Japanese Patent Application Laid-Open Publication No. 8-308853 discloses a treatment method in which tumor cells in a tissue are heated and thereby killed.
It has been proposed that where a tissue is heated or cooled by means of ablation, thermography or a thermocouple is used to monitor change in temperature of a target tissue and a tissue in the periphery thereof.